1. Field of the Invention
The invention relates to a surface plasmon resonance meter, and more particularly to a surface plasmon resonance meter with smaller volume.
2. Description of the Related Art
Conventional surface plasmon resonance meters, for example, a surface plasmon resonance meter with intensity modulation detects a specimen by light beams of particular wavelengths and incident angles. The incident angle of the light beam nears a surface plasmon resonance angle. The brightness of a reflected light beam violently changed when the incident angle thereof nears the surface plasmon resonance angle. When the surface plasmon resonance angle is changed, the brightness of a reflected light beam is obviously changed, and the variation of refractive index can be detected therefrom.
However, conventional surface plasmon resonance meters with intensity modulation have low noise ratio and low resolution. Additionally, conventional surface plasmon resonance meters with intensity modulation utilize particular optical structures, optical elements and light sources, thus requiring a complicated alignment process and increased volume. Conventional surface plasmon resonance meter with intensity modulation is thus, difficult to operate and be carried.